Inappropriate flowering

I’ve got three plants, all about three months old, which I’m keeping in 24-hour light. One of them has gone into flower ? why?
Manchester, England

Cannabis that is adapted to middle to higher latitudes uses a critical dark period as a signal to flower. The dark period lengthens throughout the summer. Adapted plants trigger in time to flower and produce viable seed.

Equatorial plants are not able to use critical dark period as a signal to start flowering because there is not much variation in photoperiod over the year. At the equator, the maximum dark period might be 13 hours with 11 hours of light. Instead of using photoperiod to determine when to flower, equatorial plants seem to use a combination of signals, including chronological age and development, as well as temperature and soil moisture cues. Hybrids of equatorial and higher latitude plants, such as Indicas from the 30th parallel, and Sativas such as Jamaican and Mexican, use photoperiod to determine flowering, but mature later than their high latitude parents.

Ruderalis is a small plant that is endogenous to the Caucasus and the steppes of Russia. The Seed Bank collected ruderalis seed from Romania. These plants from the far north are not light sensitive. Soon after they germinated and produced real leaves, they started to produce flowers. Both male and female plants produce flowers along the stem and nodes as they grow. They produce colas at the end of the season, but the flowers never ripen. The ovary behind the pistil doesn’t swell. Instead, the pistil dries and the flower shrinks.

Ruderalis was not successfully used as breeding stock because the “high,” which was buzzy and almost a headache rather than a pleasant experience, was dominant in crosses. Hybrids backcrossed with standard varieties retained their raw high characteristics and were hard to ripen. (This may be the cannabis variety that Herodotus described being used by the Scythians. They went into tents where they placed the seeded boughs on burning embers so they would smolder.)

The plant was growing for three months vegetatively before it began to flower. For this reason I suspect that some equatorial genes are involved. The plant used chronological age and size to determine when to flower.

The genetics behind this could be an unusual combination of alleles as a result of hybridization or stray pollen from another breeding room. Another possibility is that some seeds got mixed in inadvertently.

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